Fix garbled thumbnails for grayscale/CMYK JPEG cover art - #14
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ElCruncharino wants to merge 1 commit into
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Fix garbled thumbnails for grayscale/CMYK JPEG cover art#14ElCruncharino wants to merge 1 commit into
ElCruncharino wants to merge 1 commit into
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ImageLoaderJPEG::Load() hardcoded a 3-components-per-pixel row layout but never forced libjpeg's output color space, so single-component (grayscale) or 4-component (CMYK) source JPEGs produced a shorter row buffer than the copy loop assumed, reading past its end for most of each row.
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ImageLoaderJPEG::Load() copies each decoded scanline assuming 3 bytes
per pixel, but never forces libjpeg's output color space. A grayscale
(1 component) or CMYK (4 component) source JPEG then produces a row
buffer shorter or longer than the loop assumes, so most of each row
gets read out of bounds. Embedded cover art using either format shows
up as partially garbled noise.
Fix: set cinfo.out_color_space = JCS_RGB before starting decompression,
so libjpeg always hands back a 3-component RGB buffer regardless of
the source's native color space.